The subject invention relates to an improved core hole plug assembly for covering and sealing a core hole or other hole in a paved surface, a hollow or solid wall such as a concrete or block wall, or other structure.
In many locations, especially in urban environments, office parks, and shopping centers, office, industrial, commercial and other buildings are surrounded in whole or in part with paved surfaces such as but not limited to concrete paving, asphalt paving, stone or brick paving, and paving made of similar materials. The paving takes many forms, e.g. driveways, sidewalks, etc. A typical paving is a concrete slab or other paving material about four to eight inches thick. Offices, warehouses, and other industrial and commercial buildings often have solid or hollow walls made of concrete, block or other materials of various thicknesses e.g. walls having thicknesses of six to eight inches or more. Core holes or other holes, typically about three inches but sometimes greater in diameter, are sometimes formed in these paved surfaces and walls for various purposes, such as but not limited to, tests to determine if the paving or wall meets specifications, the treatment of cockroaches, ants, and various other pests, the passage of utilities through the walls, etc. Once a core has been taken from or a hole otherwise made in a paved surface, wall or other structure there usually is a need to cover and seal the hole, e.g. after a core sample has been taken, after pests have been treated, prior to the installation or after the removal of utilities, etc. Since core hole plugs are easy to install and unobtrusive or inconspicuous, rather than patching these holes, these holes are frequently covered and sealed with core hole plugs. In addition to being easy and quick to install and unobtrusive or inconspicuous, the core hole plugs have another advantage over patching the holes. Should there be a need to later gain access to the interior of the hole, the core hole plug can be removed.
However, the use of conventional core hole plugs to cover and seal core holes and other holes passing through a paved surface and into the soil beneath the paving or passing partially or completely through a wall or other structure has presented problems. Frequently, the soil has fallen away from and is spaced below the underside of the paving layer and the depth of a hole passing through a paving layer can be several inches deeper than the thickness of the paving layer to form a relatively inaccessible cavity. Hollow walls also contain relatively inaccessible cavities. The core hole plug assemblies currently in use include a cover plate, an expansible plug, a compression plate, and a bolt and nut assembly for moving the compression plate relative to the cover plate to expand and reduce the outer diameter of the expansible plug. The compression plates of these assemblies are not permanently secured to the lower end portions of the expansible plugs and the expansible plugs are not permanently secured to the cover plates. The cover assemblies are removably anchored in place by tightening the bolt and nut assemblies to expand the expansible plugs into contact with the sidewalls of the holes and are removed from the holes by loosening the bolt and nut assemblies so that the expansible plugs contract. While these core hole plug assemblies work well, the use of such core hole plug assemblies presents problems. After the core hole plug assemblies have been in place for a period of time, the plugs sometimes become stuck to the sidewalls of the holes or become otherwise hard to remove from the holes. A worker while attempting to loosen a plug from the sidewall of a hole may loosen the bolt and nut assembly too much permitting the nut and compression plate of the core hole plug assembly to fall into a wall cavity or down into a hole passing through a paved surface where the diameter of the compression plate (approximately the unexpanded diameter of the plug and only slightly less in diameter than the hole) in combination with the depth of the relatively narrow size of the hole (typically about 6 or more inches in depth and 3 inches in diameter) can make the nut and compression plate hard to retrieve or practically irretrievable. Once the nut and compression plate have become separated from the bolt of the core hole plug assembly""s bolt and nut assembly, the plug, which is not secured to the cover plate, must also be retrieved from within the hole. This further complicates matters, as the diameter of the plug approximates the diameter of the hole from which the plug must now be retrieved. Thus, there has been a need for a core hole plug assembly that solves the problems that can arise when attempting to remove a conventional core hole plug assembly from a hole.
The core hole plug assembly of the subject invention covers and seals a hole in a paved surface, wall or other structure and facilitates the easy removal of the entire core hole plug assembly from a hole without losing the nut and compression plate or the plug down within the hole or wall. The core hole plug assembly of the subject invention includes: a cover plate, a resilient expansible cylindrical plug, a compression plate, and a bolt and nut assembly for moving the compression plate relative to the cover plate to expand or reduce the outside diameter of the expansible plug. The compression plate is permanently secured to a lower end portion of the expansible plug and, preferably, the upper of the expansible plug is permanently secured to the cover plate.